Just received a pair of STAX SR 002 + SRM 002 electrostatic headphones. So far have paired them with an iPhone 6 and Cozoy Astrapi DAC/AMP for very satisfactory performance.

Am currently listening to the SRM 002s with an AK240 running DSD 64 - ambrosia!

I also have a pair of STAX SR 009s driven by a Blue Hawaii Special Edition electrostatic amplifier. Although the SR 002s don't measure up (either in performance, weight or price), they complete a nice portable rig - clearly somewhere early on the path towards the performance of the SR 009s with BHSE; a lighter touch on the low end, but with that wonderful electrostatic purity that I treasure.

I am a very happy camper My only question is whether the SR 002s will become uncomfortable in a longer listening session. I may have to look into the foamy eartips.

-- the portion that extends in to the ear is the same, with the same oval opening, only the pads/seals are different. The 002 seal is like an olive IEM seal but very thin and soft.

-- 002's fit more comfortably into my ear, and seals better.

sound:

* comparison was done using the same 003 cable, plugged into a modded 212 (with most of the 212 glare taken out; output bias is at factory setting).

* 001: sharper edges (not necessarily bad, depending on the rest of the system); leaner bass and not as much reverb (not as good a seal?). narrower stage. Mid-centric sound, gives some listener fatigue (from the 212 mid range glare, even though the 212 is modded for such glare). My feel is that the sound is thicker (not as transparent?) and harder than the 002, though only slightly.

* 002: sound is more open and more balanced, stronger bass than 001 and bouncier. No listener fatigue. The voice is a little softer than 001 (or you can say fuller, depending on the rest of the system).

Over all I definitly like the sound of 002 phones more.

However.....the 002 went channel-imbalance on me. I think it was from me not draining the charge after the last use. here is the sequence of events:

-- right after I receive the 002, four days ago, I tested the system for about 10 minutes to make sure all is working . At that time there wasn't any channel imbalance.

-- I then put the 002 (with the mini-plug cable) back into the box and put it away. * I don't remember whether the amp was on or off when I unplug the cable from the amp.

-- during this comparison test, I ran the 001 first and all was well. I then swap in the 002 driver and immediately noticed the right channel is not as full as the left. I kept listening for a few minutes and the longer I listened the less the imbalance.

-- finally I unplugged the (003 full plug) cable from the 212, plug it into a piece of conductive foam to drain the charge and left it alone for 30 minutes, then tried again.... no more channel imbalance, good sound from both sides.

Maybe the 002 sounds better because of the thinner diaphragm, but that could also be the reason of it developing the imbalance. I had the same thing happened to my ESP950 and HeAudio Jade before, it seems that this tend to happen in drivers that are either very large or using very thin diaphragm. The good news is, as long as the phones are discharged after use (either by touching the pins with your finger or by plugging into a piece of conductive foam), the imbalance does not redevelop.

So, my quick note: 002 / 003mK2 phones sound a little better in this particular setup but might require discharging after each use (If the 002 amp drains the charge when it is off, then there is no concern); 001 is sharper sounding and likes a more mellow system, it might also be a more robust model, due to the thicker diaphragm ( I have not encountered channel-imbalance in the 001/003mk1 phones, and I have three sets).